Thermostat



UNITED STATES PATENT uClinics.

wiLLmn r. rownns, ou LA ecosse, \'IsooNsiN.

THERMOSTAT.

SPECIFICATION forming part of Letters Patent No. 416,947, dated DecemberlO, 1889. l

Applicant filed January ze, 1889. Serin No. 297,626. (No man.)

To all wlw/ 11, it may concer/1,:

13e it known that l, WILLIAM l. lowicns, a citizen of the United States, residing at. La Crosse, in the county of La Grosse and State of NViseousin, have invent-:ed certain new and usefulImprovements in '1`hermostats,ol` which the following is a specification.

My invention has lor its object to provide means whereby the temperature ot' various vrooms in a building is automatically coutrolled.

In carrying outmy invention I make use of the expansive force of a lluid vaporizablc at a degree of heat approximating that which it is desired to maintain in the-building, said iluid being confined in a vessel having one or more Hexible metallic walls and located in one o f the roomsl to be heated, the i'novement of said wall being,r utilized to operatc,by means of interposed air or `other fluid, a damper or transom-actuating device. '.lhis device I may combine with means for closing the damper of a furnace by the generation of steam in an ordinary low-pressure steamheat ing boiler or in a supplemental boiler located within and heated bythe waterot a liothwaterheating system and operating by reason ot` the dillereuce in pressure ou the water ot` the maiu'boiler and the-water contained in the supplemental boiler; but this latter improve ment is the subjectmatter of a prior application, Serial No. 265,228, :tiled by me iu the 'United States Patent' Olliee February 25, 1888, and so I do not clai m here n said lastalcscrihed improvement. l

In the accompanying d1'awings,'l. `igme l is a side elevation of my improved heating appliamces, comprising a furnace and hot-water` heating boiler, located, say, in the basement lof' the/building, showing a heating-coil on aul 'upper licor and my thermostat applied thereto; This device may also be applied to the control of alow-pressurc steam-heating appa- .;ra'tns. Fig. 2 is an elevation, partly in vertisection, of the damper-operating device.

Fig. 3 is a central vertical section of the thermostat which is' shown in Figrl located Iin the same apartmentwith the heating-coils. 'Fig'. 4 is a similar view showing a moditied construction of the thermostat;.- and Fig. 5 is a sectional detailed view of the enlargement `diaphragm '(i, as shown in Fig.

in-pipe li, and showing the supplemental boiler or steam-gfmcrator hereinafter described. i f ,i

Referring to the drawings, A indicates the hot-water boiler; li, a pipe leading therefrom to theradiator C; l), anenlargement in pipe li, iuelosin,.l a vessel or steamgenerating boiler l), (see Fig. 5,) containing a body of water to be heated by the water of the circulation, and communicating by a plpe b with a chamber l, formed by inclosmg-wall 1,1 and i u i l[ is a second diaphragm placed abovediaphragm (i and secured by means of a curved wall I and bolts i, which are passed through the margins of 'both ofthe inclosing-walls A piston-rod .I is seated on the diaphragm II, and its upper end is secured to a lever K,A

pivoted at 7.'. to an arm L, projected upwardly" from the'walls ot' thel chambers described.`

One end ot' this pivoted lever'- will be provided" and of the diaplu'agl1is,l,s Shown in Fig. 2.`

with a weight M, and the other will be conf, j

neet-ed by chains with the damper N. By refph ragms (i and ll are separate, except around `75A ercnce to Fig. 2 it will be seen that the diathe margin between the confining-plates,

with a space or chamber hbetween them, forV a purpose presently described. The 'piston-- JSho rod J, as shown, in Fig. 2hasii`ts lowerlendjd,` bifurcated and a disk jattaehed to the bottomv otl these bifurcations, the diskbemg secured to the diaphragmllby means of a bolt 0, having a nuto. This bolt has au aperture l through it, which communicates at one end 'with the space h between tliediaphragms and at the other with av pipe Q, having therein a` valve (l. .lipc (2 is carried upwardly into aV room whose temperature it is desired to regulate, and there communicates with a.- thermostat, (indicated in Fig. 1` bythe letter R and shown in sectional elevation in Fig. 3.) f'lhis,`

thermostat consists of a vessel divideiltinto` curved, as shown, and under tension cause(` by the spring or the metal or by suitable coiled or flat springs, whereby it will have a tendency to enlarge the chamber containing the-volatile duid, and thereby produce a partial vacuum in said chamber, which being sealed, the pressure 011 the fiuid therein is relieved and the-boiling-point of the fiuid is lowered, in accordance with the well-known law that the boiling-point of a, liquid is determined by the pressure upon its surface,

and thereby I am enabled' to secure action of the diaphragm at a temperature lower than the normal boiling-point of the volatile'liquid. The liquid is 'introduced inl-.o chamber S through a pipe s, which is then sealed, and

a ring r serves to suspend the vessel on the` l wall ofa r'ooi'n. when it is desired to employ a iiexible` pipe or tube to connect the thermo- .stat with the damper-operating device. The

. phragm U inwardly or toward vthe opposite wall of the chamber, and thereby compress the air in the chamber T. This air .seeking escape will be forced through the connectingtube Q and into the space h between the two diaphragms G and H of the regulating device,

and in 'so doing will distend the upper diaphragm sufficiently to rock the lever and perm-it the damper to close, thus shutting o thel draft and Ilowering the temperatureofr the'roo1n.f"As the temperature is'lowered in theropm the' vapor formed inthe chamber 'S Icondenses, the diaphragm U relaxes, the

airiiows back into the chamber T, and 4the Jever, acting under the influence of the weight andthe pressure of the air upon diaphragm H', approximates toward its normal position, thus openingthel damper again and permit- 'ting the combustion in the furnace to proceed. The damper is also regulated at the boiling-point of the water inclosed in the supplemental boiler at B. When steam is generated in said boiler, it passes through pipe b to the chamber E, and, expanding therein, iiexes both, diaphragms` and operates the damper-rods. lVhen used in connection with 'urein the boiler operating in the same 'ner to raise both diaphragms and close the a low-pressure steam-heating boiler, the pipe b isconnected directly with the boiler, preferably below the waterline, the steam-pressman' damper, the chamberD and the supplemental boiler D being omitted. It is obvious ,that

'this'de'vice may be applied to open or cl'se a transom o r operate other ventilators, the only change necessary to adapt it to operate a transom being to connect the lever K with the operating-rod of the transom.

I prefer to make vessel R muchlarger than the one to which the actuating-lever is connected, and I obtain an important result' thereby. As is well known, the movement of a metallic diaphragm is comparatively limited, and none other than. a metallic diaphragm can be used in contact with volatile liquids, as such liquids are active solvents of rubber and similar-substances, and hence in the thermostat I employ a metallic diaphragm.

In the levcr'- actuating device I use a rubber diaphragm, as it is in contact with air and water only, and this diaphragm, being smaller and more iiexible than the other, a slight movement of the diaphragm of the thermostat causes a considerable -movement of the diaphragm of the ldamper-actuating device. Thus, where one diaphragm has fourv times the area of the other, a movement of one-half inch in the first will be magnified into a movement of two inches 'in the second, through the interposed column of air or other duid.

It is obvious that modifications may 'be` made ofthe forms of construction here described-ms, for example, in the construction of the thermostat-and I have` shown in Fig. 4 such a modification. In this figure the chamber S is formed by two corrugated diaphragms, both of which are iiexible, their 'margins being secured' together and inclos'ed within chamber T. Both of said diaphragms are distended by the vaporization of the fluid in chamber S, and 'operate to force the airout of chamber T. It is also obvious that the thermostat may be used with a damper or transom regulating device having only one diaphragm-as H, for example-andthe provisions for-actuating the damper may be omitted.

Theyare conveniently combined,- however,

and it may be found convenient to use both devices in combination.

The device above described is adapted to control the temperature within a very narrow range, and I regard as the chief improvement the provisions, for utilizing an air or other iiuid piston'int'crposed between the thermostat and tlie damper-actuating mechanism, as this-improv'ement renders it easy to control lthe IOO.

damper of a furnace locatedi ata distance from the thermostat Without the intervention of rod or other connecting devices,- the use of which is attended with many objections. By means of this combination of the two diaphrag'ms'with theJluid-piston inter-4 posedfI am able to make a rigid connection of the`operating devices with the smaller an'd nection were made direct to the metallic diaphragm at any particular point, (as thecenten) the diaphragm would soonbe destroyed more elastic of the two, whereas, ifv such conby its action under pressure, the pressure be'- ing'exerted upon all its surfaces, while the resistance'is only at one point where the'piston "is connected; but by my method vthe pressure is equal upon each side of the metallic diaphragm and distributed over every point of the same, thus making it practicable to use a very still have it durable and lasting. ly means of this combination I am also able to increaspI 4the movement of the piston as compared the liquid, a second ehamberand apipeleadposed air ing therefrom, whereby to confine a body of air or other uid in contact withsaid flexible wall, and a pressure-chamber with which said pipe communicates, and having` a diaphragm or other piston, and suitable opcratingdevices actuated by said diaphragm, whereby the movement-of the wall of the vaporizingchamber is transmitted through the interor other fluid column to the diaphragm of the pressure-chamber, substantially as described.

2. In a heat-regulating apparatus, a double diaphragm composedof two elastic sheets, one of which forms one wall of a pressurechamber to operate by pressure ot steam, the

light and sensitive diaphragm and other designed to operate by a Huid pressure .transmitted through a pipe andV caused by the volatilization of a liquid Vaporizingat about the temperature sought te be mainx tained, the diaphragms heilig so' arranged that the effect desired is produced by the aetion of either cause independently of the l other, substantially as described.

Inaheat-regulating device, av'aporizingn' chamber to contain a volatile liquid, a movj able side or wall normally under tension,

such tension tending to enlarge the vaporizing-chamber and thereby produce a lowering ot' the pressure upon `the contents thereof and consequently a lower point of vaporization for the purpose of securing action at a lesser degree of heat-,as and for the purpose specified. Y

4. In a heat-controlling device, the `combination, with a thermostat, of a damper or i ventilator actuating device comprising `two diaphragms secured within a pressure-chamber and having a space between their opposing surfaces, a-tube communicating with said space and with the thermostat, and a steamgenerating boiler communicating with the chamber below the diaphragms,substantiallyV i as described.

Witnesses:

FREDERICK C. GOODWIN, T. D. BUTLER.

WILLIAM RrowERs. f 

